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The East Asian finless porpoise, Neophocaena asiaeorientalis sunameri, is an endangered species that inhabits the coastal marine environments of East Asia. In the present study, we investigated the overall infection status of anisakid nematodes in East Asian finless porpoises from three sea sectors off the Korean Peninsula. The genetic diversity and population genetic structure of the identified nematode species were evaluated. The prevalence of all stages of anisakid nematodes collected from the stomach was 57.55% (61 among the 106 porpoises examined), and 16 of the hosts were found to have adult worms. The mean number of infected adults was 211 (± 419.54, 5–1455 per host). Only one species of anisakids, Anisakis pegreffii, was identified from randomly selected worms by molecular approaches. Analysis of the mitochondrial (mt) cox2 partial gene in 50 newly generated sequences of A. pegreffii revealed 24 haplotypes, including 14 new haplotypes. We observed below-average levels of nucleotide diversity and haplotype diversity compared to other seas around the world. The mtDNA cox2 haplotypes of the species in the three Korean sea areas showed no genetic structure, suggesting well-connected gene flow within these areas. This study represents the first record of a definitive host of A. pegreffii in Korean waters, providing important information regarding anisakids genetic diversity in the cetacean species inhabiting limited regions. [ABSTRACT FROM AUTHOR]

Ticks are ectoparasites responsible for the transmission of various pathogens to vertebrates. They represent one of the major threats to livestock production worldwide due to their impact on the health, production and welfare of livestock destined for human consumption. The development of resistance to the main families of ixodicides used for their control has led to the search for new alternatives, where microbial control is an option. The use of microbial control agents against the tick Rhipicephalus microplus is reviewed in this paper. Bacteria such as Bacillus thuringiensis, Serratia marcescens and Staphylococcus spp. the nematodes Steinernema spp. and Heterorhabditis spp. as well as the fungi Metarhizium anisopliae and Beauveria bassiana are the most studied organisms for use as biological control agents against ticks. Laboratory, stable and field trials with free-living and parasitised ticks have shown that microbial agents can control both susceptible and ixodicide-resistant tick populations. However, multidisciplinary studies using novel tools like genomics, transcriptomics and proteomics should be carried out to understand the virulence factors which microbial agents use to induce pathogenesis and virulence in ticks. In addition, applied research will be carried out with the aim of improving techniques for large-scale application, as well as the improvement of cultivation, storage, formulation and application methods. [ABSTRACT FROM AUTHOR]

Pangolins are susceptible to a variety of gastrointestinal nematodes due to their burrowing lifestyle and feeding habits, and few parasitic nematodes have been reported. Here, a Chinese pangolin with old wounds on its leg and tail was rescued from the Heyuan City, Guangdong Province. The cox1 and SSU rRNA of the worms from the intestine of the Chinese pangolin had the highest sequence identity of 89.58% and 97.95% to the species in the infraorder Spiruromorpha. The complete mitogenome of the worm was further assembled by next-generation sequencing, with a size of 13,708 bp and a GC content of 25.6%. The worm mitogenome had the highest sequence identity of 78.56% to that of Spirocerca lupi, sharing the same gene arrangement with S. lupi and some species in other families under Spiruromorpha. However, the mitogenome between the worm and S. lupi showed differences in codon usage of PCGs, sequences of NCR, and tRNA secondary structures. Phylogenetic analysis showed that the worm mitogenome was clustered with S. lupi in the family Thelaziidae to form a separate branch. However, it is still difficult to identify the worm in the family Thelaziidae because the species in the family Thelaziidae are confused, specifically S. lupi and Thelazia callipaeda in the family Thelaziidae were separated and grouped with species from other families. Thus, the parasitic nematode from the Chinese pangolin may be a novel species in Spiruromorpha and closely related to S. lupi. This study enriches the data on gastrointestinal nematodes in the Chinese pangolin. [ABSTRACT FROM AUTHOR]

During bacterial and viral pathogen investigation of 30 specimens of bats captured in periurban forest areas in the city of Belém, Pará, Brazil, a case of cerebral filariasis was observed. In the course of histopathological examination, adult filariae were found in pseudocystic cavities brain of Molossus barnesi (Molossidae) and classified morphologically as Litomosoides by the shape of the spicules—left spicule with a handle longer than the blade; right spicule curved, with a sclerotized heel supporting a dorsal notch; the area rugosa constituted by a ventral band of small longitudinal crests; tail rounded in males; long esophagus with a slightly glandular distal portion; and a muscular bent vagina. All the specimens lack a stoma (buccal capsule). We compared our filarioids with the description of specimens of Molossinema wimsatti. Morphological characteristics of M. wimsatti resemble the genus Litomosoides. Thus, we believe that M. wimsatti is a synonym of L. molossi Esslinger, 1973, and filarioid specimens from material reported by Lichtenfels et al. (Trans Am Micros Soc 100:216–219, 1981) and from de Souto et al. (J. Helminthol 1195:e65, 2021) most probably correspond to Litomosoides. We suggest that the reduction of the buccal capsule may be attributable to the ectopic location. No evidence of tissue responses by the host was observed. This is the first record of Litomosoides infecting brain tissue of Molossus barnesi from Brazil, representing a record of a new host species. More specimens of bats should be examined in order to find filarioids in the brain and verify its taxonomic position using molecular techniques. [ABSTRACT FROM AUTHOR]

Cardio-pulmonary parasites, such as Angiostrongylus vasorum, Crenosoma vulpis, and Eucoleus aerophilus, pose a significant concern on account of pulmonary and cardiac problems they induce in dogs. While the red fox is known to be a key reservoir host for A. vasorum and may also play a role in transmitting C. vulpis and E. aerophilus, there has been no recent research on these parasites in foxes from Sardinia, with the most current studies dating back to 1986. A survey was conducted on red foxes in Sardinia, where a total of 51 foxes were collected, necropsied, and examined for adult worms in their hearts and lungs. The worms were identified using morphometric analysis and molecular methods. The results showed a 54.9% overall prevalence at dissection: 45.1% of the foxes were positive for E. aerophilus, 17.6% for C. vulpis, and 13.7% for A. vasorum. The molecular analyses validated the morphological characterization. In comparison to previous research, which found 13 out of 85 foxes to be positive for A. vasorum with a prevalence rate of 15.3% and 1 for E. aerophilus with a prevalence of 1.2%, this study showed an increased prevalence of E. aerophilus and C. vulpis, and a decrease in the prevalence of A. vasorum. These results indicate that the red foxes in Sardinia represent a reservoir host for cardio-pulmonary nematodes and it should be considered in the differential diagnosis of respiratory distress syndrome in dogs. [ABSTRACT FROM AUTHOR]

Being able to systematically detect parasitic infection, even when no visual signs of infection are present, is crucial to the establishment of accurate conservation policies. The nematode Anguillicola crassus infects the swimbladder of anguillid species and is a potential threat for eel populations. In North America, naïve hosts such as the American eel Anguilla rostrata are affected by this infection. The accidental introduction of A. crassus following restocking programs may contribute to the actual decline of the American eel in Canada. We present a quantitative real time PCR-based method to detect A. crassus infection in final and intermediate hosts. We tested two protocols on samples from different geographical origins in Canada: 1) a general detection of A. crassus DNA in pools of young final hosts (glass eels) or crustacean intermediate hosts 2) a detection at the individual scale by analyzing swim bladders from elvers, or from adult yellow and silver eels. The DNA of A. crassus was detected in one pool of zooplankton (intermediate host) from the Richelieu River (Montérégie-Québec), as well as in individual swim bladders of 13 elvers from Grande and Petite Trinité rivers (Côte-Nord-Québec). We suggest that our qPCR approach could be used in a quantitative way to estimate the parasitic burden in individual swim bladders of elvers. Our method, which goes beyond most of previous developed protocols that restricted the diagnosis of A. crassus to the moment when it was fully established in its final host, should help to detect early A. crassus infection in nature. [ABSTRACT FROM AUTHOR]

Anisakidosis is a foodborne zoonotic infection induced by members of the family Anisakidae via the consumption of raw or undercooked fish such as sushi and sashimi. Identifying anisakid larval species is critical for the epidemiology and diagnosis of diseases caused by them. This study aimed at identifying Anisakis larvae collected from marine fish in Egyptian waters based on morphological characteristics and molecular analysis. Thirty marine fish coral trout, Plectropomus areolatus, were collected from Hurghada, Red Sea, Egypt, to investigate larval nematodes of the genus Anisakis. The larvae were detected encapsulated in the peritoneal cavity and muscle of the fish host. This examination revealed that anisakid larvae naturally infected 19 fish specimens with a prevalence of 63.33% and a mean intensity of 4.1 ± 0.40. Most of them (68 larvae: 71.57%) were found in the musculature. Morphological and morphometric analyses using light and scanning electron microscopy revealed a head region with a prominent boring tooth, inconspicuous lips, and a characteristic protruded cylindrical mucron. All larvae in this study possessed the same morphology as Anisakis Larval type I. Molecular analysis based on ITS region using maximum likelihood and Bayesian phylogenetic methods confirmed them as Anisakis typica. This is the first study to identify A. typica larvae from the commercial fish coral trout P. areolatus in Egyptian waters using morphological and molecular methods. [ABSTRACT FROM AUTHOR]

Nematodes of the genus Dictyocaulus are the causative agents of parasitic bronchitis and pneumonia in several domestic and wild ungulates. Various species have been described in wild cervids, as the case of Dictyocaulus cervi in red deer, recently described as a separate species from Dictyocaulus eckerti. In Italy, information on dictyocaulosis in wildlife is limited and often outdated. In this work, 250 red deer were examined for the presence of Dictyocaulus spp. in two areas of the Italian Alps (n = 104 from Valle d'Aosta, n = 146 from Stelvio National Park), and the retrieved lungworms were molecularly characterized. Lungworms were identified in 23 and 32 animals from Valle d'Aosta and Stelvio National Park, respectively. The nematodes, morphologically identified as D. cervi, were characterized molecularly (18S rDNA, ITS2, and coxI). Consistently, almost all specimens were found to be phylogenetically related to D. cervi. Three individuals, detected from both study sites and assigned to an undescribed Dictyocaulus sp., clustered with Dictyocaulus specimens isolated from red deer and fallow deer in previous studies. Within each of D. cervi and the undescribed Dictyocaulus sp., the newly isolated nematodes phylogenetically clustered based on their geographical origin. This study revealed the presence of D. cervi in Italian red deer, and an undetermined Dictyocaulus sp. that should be more deeply investigated. The results suggest that further analyses should be focused on population genetics of cervids and their lungworms to assess how they evolved, or co-evolved, throughout time and space and to assess the potential of transmission towards farmed animals. [ABSTRACT FROM AUTHOR]

Cucullanus pinnai has been divided in two subspecies (C. pinnai pinnai and C. pinnai pterodorasi) based on the morphology of oesophastome. While C. pinnai pinnai apparently shows low host specificity and broad geographic occurrence, with certain morphological variations, C. pinnai pterodorasi was reported once, parasitizing Pterodoras granulosus. We used an integrative taxonomic approach to evaluate whether or not populations of C. pinnai pinnai from Trychomycterus spegazzinii (Escoipe River, Argentina) and Pimelodus fur (Miranda River, Brazil), and of C. pinnai pterodorasi from Pterodoras granulosus (Miranda River, Brazil) are conspecific. Parasites were observed using light microscopy and genetically characterized based on partial sequences of the 18S and 28S rDNA, ITS1-5.8S-ITS2, and COI mtDNA. Phylogenies were reconstructed and the Generalized Mixed Yule Coalescent (GMYC), Poisson Tree Process (bPTP), and Automatic Barcode Gap Discovery (ABGD) were used for species delimitation purposes. The present samples formed well-supported monophyletic assemblages, corroborating in part the results of morphological analyses; however, they grouped according to geographic origin. Species delimitation suggested conspecificity of C. pinnai pinnai with C. pinnai pterodorasi from Brazil; consequently, the morphology of oesophastome may be an intraspecific variation. Results also indicated that C. pinnai may represent a species complex as samples from Argentina were suggestive of an independent specific entity. However, definitive affirmations are premature, since there is no autapomorphy for separating C. pinnai from Brazil and Argentina and sampling was limited to three host species from two river basins. The phylogenetic reconstructions also confirmed the artificiality of some genera within Cucullanidae. [ABSTRACT FROM AUTHOR]

First stage larvae of an unknown lungworm (Protostrongylidae) were isolated in the feces of a wild reindeer (Rangifer tarandus) from Taimyr, Russia. Larvae were 365–366 μm long and had a tail spike lacking a dorsal spine. DNA analyses using BLAST showed that nuclear sequences obtained (LSU rDNA, 825 bp and ITS2 rDNA, 395 bp) were highly similar (99.50% and 98.88% identity, respectively) to an isolate of Orthostrongylus macrotis (GenBank: EU595592.1) from North America. It cannot be confirmed whether these larvae represent an uncharacterized species of Orthostrongylus or can be referred to O. macrotis, a species that has historically only been reported from the Nearctic. This is the first report of lungworms attributable to Protostrongylinae in R. tarandus across its vast geographic in the Holarctic. [ABSTRACT FROM AUTHOR]

In horses, the nematodes of the Strongylidae family are the most important due to their prevalence and pathogenicity. Sanitary plans include parasite control based on chemical anthelmintics. Among these, the benzimidazole compounds have been used since the 1960s to control the nematode Strongylus vulgaris. Its inappropriate use resulted in the development of resistance in parasites with a shorter biological cycle, such as the small strongyles. Currently, the genera that make up this group show widespread resistance to all chemical treatments available in veterinary medicine, except for macrocyclic lactones, where less effective action has been detected. The need to find alternative routes for its control is recognized. International organizations and markets are increasingly restrictive in the allowed levels of drugs in products of animal origin, so one of the drawbacks is the permanence of chemical compounds in tissues. Therefore, other tools not chemically based are proposed, such as the biological control of gastrointestinal nematodes. Various research groups around the world have carried out tests on the control capacity of the nematophagous fungus Duddingtonia flagrans against this group of parasites. The objective of this review is to compile the different tests that are available on biological control in this species, in in vivo and in vitro tests, and the possible incorporation of this tool as an alternative method of antiparasitic control in an integrated control scheme of parasites. [ABSTRACT FROM AUTHOR]

In South America, the family Philometridae is represented by several genera and species. In particular, Philometra and Philometroides are the most speciose genera. In Argentina, only Philometroides tahieli has been reported so far. The main objective of this study was to analyze the phylogenetic relationship between Ps. tahieli and other South American philometrids using molecular data. The molecular analysis was performed using a female specimen of Ps. tahieli found on the opercular muscle of a juvenile Micropogonias furnieri from brackish waters in Argentina. Phylogenetic relationships were studied based on partial sequences of the 18S rDNA and 28S rDNA genes. In the 18S rDNA tree, Ps. tahieli was mainly grouped with other Philometroides from freshwater hosts from China, sharing the site of infection (head tissues or muscles). In the 28S rDNA tree, obtained with fewer sequences, Ps. tahieli is related species from subcutaneous tissues of head. This study contributes with information on philometrids and confirms the presence of different lineages among South American species, with Ps. tahieli representing a new one. Further studies on South American species using more molecular markers and new morphological characters will improve our knowledge of philometrid biodiversity and phylogeny. [ABSTRACT FROM AUTHOR]

This study investigated the influence of temporal and seasonal (i.e., rainy and dry seasons) in communities and infracommunities of metazoan parasites in Pimelodus ornatus, a Siluriformes from the Amazon River in the state of Amapá, in northern Brazil. A total of 144 fish were collected during 2020 and 2021. In 2020, five species of parasites were found (1 Monogenea, 3 Nematoda, and 1 Cestoda), and in 2021, seven species of parasites were found (1 Monogenea, 3 Nematoda, 1 Cestoda, 1 Digenea, and 1 Crustacea). In 2020, Spirocamallanus inopinatus was dominant, while in 2021, Contracaecum sp. was dominant. Brillouin diversity, species richness, and evenness were higher in 2021. There were differences for some parasite infracommunities between years and between seasonal periods. Brillouin diversity and species richness were higher in the rainy season, but there were no differences in evenness and Berger-Parker dominance between the seasonal periods. Temporal and seasonal variations were mainly influenced by rainfall levels, oxygen levels, and environmental temperature and, later, by the availability of infective stages of parasites in the environment and the size of the hosts. Lastly, the influence of the temporal and seasonal variations on the structure of communities and infracommunities of parasites was weaker than expected due to the low infection rates of the majority of parasites found. [ABSTRACT FROM AUTHOR]

Enterobius vermicularis, a nematode parasite with a global distribution causes enterobiasis in schoolchildren and is considered a neglected parasite. An understanding of the prevalence and genetic diversity of enterobiasis is crucial for appropriate control measures. Therefore, the objectives of this research were to study the prevalence and genetic diversity of E. vermicularis in schoolchildren from lower northern Thailand, based on cytochrome c oxidase subunit I (COI) and internal transcribed spacer 2 (ITS2) sequences. Using the scotch tape technique, 7.4% (188/2544) of schoolchildren from 21 primary schools were found positive for E. vermicularis eggs, which is a relatively low infection rate. Phylogenetic trees of partial COI sequences (397 bp) revealed similar topologies using maximum likelihood (ML) and neighbor-joining (NJ) methods and identified E. vermicularis type A (105 sequences) and B (1 sequence). Haplotype network analysis of the COI sequences demonstrated a high haplotype diversity (Hd = 0.9028). In contrast, phylogenetic analysts of a 343 bp region of the ITS2 locus (52 sequences) revealed a monophyletic group. More sequence analyses of E. vermicularis from humans and other hosts in Thailand are necessary to better understand the genetic diversity of this parasite. [ABSTRACT FROM AUTHOR]

Variable platyfish, Xiphophorus variatus (Meek, 1904) (Cyprinodontiformes: Poeciliidae) and eastern mosquitofish, Gambusia holbrooki Girard, 1859 (Poeciliidae) from earthen ponds in west central Florida were examined for parasitic infections. At necropsy, we observed myriad nematodes (adults and eggs), which we identified as Huffmanela cf. huffmani, infecting the swim bladder, gonad, and visceral peritoneum. Nucleotide sequences (small subunit ribosomal DNA, 18S) of H. cf. huffmani from variable platyfish and eastern mosquitofish were identical; likewise for newly obtained 18S sequences of Huffmanela huffmani Moravec, 1987 from the swim bladder of red breast sunfish, Lepomis auritus (Linnaeus, 1758) (Centrarchiformes: Centrarchidae) and warmouth, Lepomis gulosus (Cuvier, 1829) from the San Marcos River (type locality for Huffmanela huffmani Moravec, 1987), Texas. The sequences of H. huffmani and H. cf. huffmani differed by 7 (1%) nucleotides. Pathological changes comprised proliferation of the tunica externa of the swim bladder in low-intensity infections in addition to inflammation, proliferation, and tissue necrosis of swim bladder, peritoneum, and gonad in high-intensity infections. The lesion was severe, affecting the cellular constituents of the swim bladder wall and reducing the size of the swim bladder lumen; potentially reducing swim bladder physiological efficiency. The present study is the first record of a freshwater species of Huffmanela Moravec, 1987 from beyond the San Marcos River, first record of a species of Huffmanela from a livebearer, first nucleotide sequences and phylogenetic analysis for Huffmanela, and first evidence that an infection by a species of Huffmanela causes pathological changes that could impact organ function. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate a method of targeted selective treatment (TST) of Morada Nova lambs, based on the average daily weight gain (DWG). For this, 114 lambs in the rainy and 102 in the dry season were randomized into three treatments: control (CT), routine (RT, treated every 42 days), and targeted selective (TST, treated according to DWG). Packed cell volume (PCV) and eggs per gram of feces (EPG) tests were performed. The anthelmintic resistance of parasites was assessed by the EPG count reduction test (FECRT), RESISTA-Test©, and molecular test. For CT, RT, and TST groups, the following results were obtained: mean EPG values were 4665.1, 3063.5, and 3462.1 in the rainy season and 4475.1, 1341.7, and 2863.4 in the dry season, respectively; mean PCV values were 32.1, 33.4, and 32.3% in the rainy season and 33.9, 36.0, and 35.1% in the dry season; mean DWG readings were 0.087, 0.101, and 0.094 kg in the rainy season and 0.102, 0.113, and 0.112 kg in the dry season; efficacies of levamisole in FECRT were 66.4, 24.1, and 76.4% in the rainy and 90.7, 12.4, and 64.8% in the dry season, respectively; in the RESISTA-Test©, the LC50 values were 0.482, 1.926, and 0.117 µg.mL−1 in the rainy and 0.437, 0.851, and 0.045 µg.mL−1 in the dry season, respectively; the frequencies of the homozygous-resistant genotype were 57.1, 71.4, and 40.0% in the rainy and 47.8, 55.9, and 41.9% in the dry season. In conclusion, TST reduced the development of resistance through refugia maintenance, without productive losses, contributing to the sustainability of sheep breeding. [ABSTRACT FROM AUTHOR]

The objective of this controlled study was to determine the anthelmintic efficacy of eprinomectin 5% w/v extended-release injection (Eprinomectin ERI; LONGRANGE®, Boehringer Ingelheim Animal Health) against primarily ovine-adapted gastrointestinal strongylid nematode (GIN) parasites in naturally infected young cattle. Eighteen calves which grazed on a sheep-dominated mixed sheep-cattle farm were randomly allocated into two equal groups (saline [control] or Eprinomectin ERI, administered each at 1 mL/50 kg body weight once subcutaneously), treated and euthanized 14 days thereafter for a differential GIN count. Ten species of strongylid nematodes were recovered from the control calves (ovine-adapted Haemonchus contortus, Teladorsagia circumcincta, Trichostrongylus colubriformis, Cooperia curticei, Nematodirus battus, Chabertia ovina; bovine-adapted Ostertagia ostertagi, Cooperia oncophora, Nematodirus helvetianus; ʻgeneralistʼ Trichostrongylus axei). Adult GIN counts ranged from 1,540 to 5,244 for the control calves and from zero to 110 for the Eprinomectin ERI-treated calves. Accepting the International Cooperation on Harmonisation of Technical Requirements for Registration of Veterinary Medicinal Products anthelmintic guidelines criteria on adequacy of infections to be demonstrated in the control animals, this study showed that Ch. ovina, C. curticei, H. contortus, N. battus, T. axei, and T. colubriformis were reduced significantly (p < 0.0001) by ≥ 98.7% in the animals treated with Eprinomectin ERI. In conclusion, Eprinomectin ERI treatment was efficacious against a range of ovine-adapted nematode parasites in naturally infected young cattle. [ABSTRACT FROM AUTHOR]

Infections with parasitic helminths cause severe debilitating and sometimes lethal diseases in humans and domestic animals on a global scale. Unable to synthesize de novo their own fatty acids and sterols, helminth parasites (nematodes, trematodes, cestodes) rely on their hosts for their supply. These organisms produce and secrete a wide range of lipid binding proteins that are, in most cases, structurally different from the ones found in their hosts, placing them as possible novel therapeutic targets. In this sense, a lot of effort has been made towards the structure determination of these proteins, but their precise function is still unknown. In this review, we aim to present the current knowledge on the functions of LBPs present in parasitic helminths as well as novel members of this highly heterogeneous group of proteins. [ABSTRACT FROM AUTHOR]

Due to the recent recovery of brown bear populations in Central Europe, information about their ascarid parasite, Baylisascaris transfuga is necessary as the parasite represents a part of natural ecological networks. B. transfuga can lead to larva migrans syndrome in accidental hosts, but its zoonotic potential has not been confirmed. The resent study compares development of larva migrans in infected mice inoculated with two infectious doses (ID 200 and ID 2000) of B. transfuga embryonated eggs, and the clinical manifestation to evaluate the pathogenicity of the larvae. Histopathology revealed that the liver was the most severely infected organ. The moderately infected organs included lung, brain, skeletal muscles and jejunum and the less infected ones were the eyes, heart, kidneys and spleen. The high pathogenicity of B. transfuga to mice was reflected in high mortality (33,3%) after infection, with mortality increasing with higher infectious dose. The results extend the knowledge of the interaction of B. transfuga and its aberrant hosts and contribute to the understanding of the epidemiology and transmission of this bears roundworm. [ABSTRACT FROM AUTHOR]

Eurasian beaver (Castor fiber) is a well-established faunal element in the Czech Republic, even though, historically, its populations were almost eradicated in this region. Nowadays, its distribution and population density are well monitored; nonetheless, the beaver's parasites, as potential threats to the environment, are often neglected in wildlife management. Therefore, we investigated the endoparasitic helminth diversity of 15 beaver individuals from three collection sites in the Czech Republic. Three parasite species were collected: Stichorchis subtriquetrus (Digenea), Travassosius rufus, and Calodium hepaticum (Nematoda), of which the two nematode species were reported for the first time from C. fiber in the Czech Republic. The highest prevalence and intensity of infection were observed in S. subtriquetrus (P = 93%, I = 1–138), while the two other species were collected only from one beaver individual. Subsequent analysis of the genetic diversity of the specimens using highly variable genetic markers revealed a weak population structure among the individuals collected from different beaver hosts. There was only a weak association of COI haplotypes with geography, as the haplotypes from the Berounka basin formed homogeneous groups, and individuals from the Dyje basin and Morava partially shared a haplotype. Even though common population genetic markers (i.e., microsatellites) did not reveal any structure in the hosts, our results suggest that the genetic diversity of their parasites may shed more light on population partition and the historical migration routes of Eurasian beavers. [ABSTRACT FROM AUTHOR]

Cosmocercid nematodes have been documented with much criticism due to the numerous inaccurate descriptions, redescriptions and synonymisation of found species. This is due to indistinguishable characters of females and the lack of male specimens found. Consequently, the species C. ornata is the most commonly found species worldwide and the only species of the genus reported in South Africa. In the present study, we found Cosmocerca in three different amphibian species, namely Cacosternum boettgeri, Kassina senegalensis and Phrynomantis bifasciatus. Based on differences in the shape of the gubernaculum and number of papillae, the found nematodes were assigned to three new species namely C.daly n. sp., C. monicae n. sp. and C. makhadoensis n. sp. Descriptions of species are followed by pairwise and phylogenetic analysis of partial ITS-28S sequences. All three species were found only in their host types from distant localities. Therefore, we hypothesise that host specificity of Cosmocerca from South African amphibians might be rather high and that the presence of C. ornata throughout South Africa is rather doubtful. [ABSTRACT FROM AUTHOR]

Rhabdias Stiles and Hassal, 1905 comprises approximately 90 species of parasitic lung nematodes of amphibians and reptiles that have a wide distribution, with 21 species occurring in the Neotropics. In the present study, we describe Rhabdias waiapi n. sp. found parasitizing the lungs of the anuran species Pristimantis chiastonotus from the Amazon Biome in the Amapá State, Northern Brazil. The new species is characterized by having an elongated body, expansions of the cuticular inflation in the anterior end that become more discrete along the body, an anterior end with a slight constriction at the level of the esophageal apex with four rounded subapical elevations of the body wall, six lips, four near the edge of the oral opening and two more distant lateral ones, and a gradually tapering elongated tail. In addition, molecular analyses and phylogenetic reconstructions were made, with sequences from the coding region of the mitochondrial cytochrome c oxidase subunit I gene. Those results strongly support the status of the new taxon, which formed a poorly supported clade with Rhabdias sp. 5 from Anolis brasiliensis from Northeast Brazil. Rhabdias waiapi n. sp. is the 19th species of the genus described in the Neotropics for amphibians, the 10th in Brazil, the second described from hosts of the family Strabomantidae from the Neotropical region, and the first amphibian nematode species described in the Amapá State. [ABSTRACT FROM AUTHOR]

Nematodes of the family Philometridae Baylis & Daubney, 1926 (Dracunculoidea Stiles, 1907) are generally poorly known, and there are many taxonomic issues within the family. Philometrids are parasites of fish and are found in various locations throughout the host, including within the subcutaneous tissues and musculature, the abdominal cavity and gonads; vast sexual dimorphism often means the males are not collected, leading to many species being described solely on female characteristics. Although there have been a number of studies utilising molecular data, the vast majority of species are yet to be sequenced. This study undertook genetic sequencing of 15 recently described species of philometrids across 4 genera, many of which were from specimens collected from waters off Australia. All of the sequences obtained were closely related with representatives of the family Philometridae. Species were found to be distributed in the phylogenetic trees within 4 clades based on a combination of site of infection within the host and host habitat. Family of host and geographical location was not as important for position within the trees. Clade A contained philometrids collected from the abdominal cavities and head tissues of South American freshwater fish. Clade B contained philometrids primarily from the abdominal cavities of freshwater European cyprinids. Clade C contained philometrids primarily from the ovaries of marine fish. Clade D contained philometrids from the body tissues of marine and freshwater fish. The potential co-evolutionary patterns between philometrids and their fish hosts are highlighted as an area of future research. This research also highlighted the importance of correct identification of any sequenced specimen. [ABSTRACT FROM AUTHOR]

Aedine mosquitoes go through unfavorable periods as dormant eggs. However, extended dormancy times lead to a depletion of egg reserves, which might be partially compensated by changes in larval-feeding behavior. Changes in larval behavior may also be induced by parasitism by mermithids probably as a strategy to reduce the impact of the parasite on the host. The most abundant floodwater mosquito in southern South America is Aedes albifasciatus (Diptera: Culicidae), a species naturally parasitized by Strelkovimermis spiculatus (Nematoda: Mermithidae). This study aimed to evaluate the behavior of fourth-instar larvae of Ae. albifasciatus from eggs with 2, 4, and 6 months of dormancy, parasitized or not by S. spiculatus. To achieve this, eight categories of behavior were defined, and then, each individual was observed for 5 min, and its behaviors and their duration were recorded. The behaviors with the highest percentage of observation time were still (50.1%) and wriggle swimming (33.6%), while those with the lowest percentage of observation time were those involving active foraging (less than 8%). A great variability in the behaviors was observed among individuals within the same treatment. The type and duration of each behavior did not vary in relation to egg dormancy time or parasitism, but parasitism affected the level of larval activity. Parasitized larvae performed, on average, fewer behaviors than non-parasitized larvae. This result supports the hypothesis that S. spiculatus parasitism affects the behavior of Ae. albifasciatus larvae by reducing their level of activity. [ABSTRACT FROM AUTHOR]

Classic approaches for antemortem identification of gastrointestinal nematodes (GIN) require coproculture of eggs and morphological examination. While adequate for diagnosis, many PCR techniques cannot easily quantify mixed infections without controls and/or standard curves. Herein, we developed a simple and rapid test for differentiating and quantifying mixed infections of GIN using PCR products separated by capillary electrophoresis. Among the cattle GIN, the ITS2 region is sufficiently distinct in length to delineate among the most common infecting genera, Ostertagia ostertagi = 373 bases (b), Haemonchus contortus (placei) = 366b, Cooperia punctata (oncophora) = 376b, Trichostrongylus axei = 372b, and Oesophagostomum radiatum = 357b. Conserved primers were synthesized that span the ITS2 where one primer was fluorescently labeled with 6-FAM. DNAs from infective L3 were PCR amplified then loaded onto an ABI 3130 sequencer adapted for size fragment analysis. Resulting peak amplitudes were both diagnostic and quantitative on a relative basis. As proof of principle, quantification was performed on PCR fragments from mixed species pairs of Ostertagia ostertagi, Cooperia punctata, and Haemonchus contortus and analyzed using Gene Marker V1.85 software. In all cases, linear responses were observed where R2 > 0.97 and line slopes ranged between 0.90 and 1.1. When tested on eggs from naturally infected animals, the assay showed superior results on two farms when compared to coproculture and morphological identification. Using wildlife-derived samples, results coincided well with deep amplicon sequencing. The assay is adaptable to large-scale studies, does not require comparative PCR controls, and should be compliant with GIN from small ruminant livestock. [ABSTRACT FROM AUTHOR]

Parasite ecology has recently focused on elucidating patterns and processes that shape helminth communities in avian hosts. However, helminths parasitizing gamebirds are still poorly understood. Here we describe the gastrointestinal nematode fauna of Swainson's spurfowl, Pternistis swainsonii (Phasianidae) and helmeted guineafowl, Numida meleagris (Numididae), collected at three and four localities, respectively, in South Africa and analyze the prevalence, mean abundance and diversity of their helminth communities. Eleven nematode species were collected from spurfowl, which had a mean number of nematode species per host of 3.01 ± 0.18, whereas guineafowl harboured 15 nematode species, with a mean number of nematode species per host of 3.93 ± 0.12. Focusing on the most prevalent species, we also asked if host sex and/or age were associated with infracommunity structure with regard to nematode counts and species richness, as well as the species and taxonomic composition of infracommunities. While pooling data of nematode species masked the influence of host characteristics on helminth communities, analysis of individual nematode species revealed a number of patterns. In particular, adult female bias was seen in Tetrameres swainsonii in spurfowl and in Allodapa dentigera and Gongylonema congolense in guineafowl; Acuaria gruveli reached higher numbers in adult spurfowl than in juveniles, and helminth infracommunities in juvenile male guineafowl were more species rich than those in adult males. Combined, our results suggest that helminth communities of spurfowl and guineafowl are associated with a complex interplay of numerous factors, including host characteristics, parasite traits and environmental conditions. [ABSTRACT FROM AUTHOR]

This study investigated the distribution of nematode larvae of Anisakidae and Raphidascarididae (genera Anisakis and Hysterothylacium) in Trachurus trachurus (Linnaeus, 1758) in the Ligurian and central-northern Tyrrhenian Seas. The relationship between the number of parasites and the length and weight parameters of the fish was assessed, and the possible effect of the parasites on the condition factor was evaluated. A total of 190 T. trachurus specimens were collected in July 2019. Parasites were found in 70 individuals. A total of 161 visible larvae were collected in the viscera. Morphological analysis revealed the presence of Anisakis spp. in 55 fish and Hysterothylacium spp. in 15 fish, while 5 fish showed coinfection with both genera. The specimens subjected to PCR (n = 67) showed that 85% of the Anisakis larvae analyzed belonged to the species A. pegreffii, while the remaining 15% belonged to hybrids of A. pegreffii-A. simplex (s.s.). A total of 58% (n = 7) of the Hysterothylacium larvae analyzed belonged to the species H. fabri, while 42% belonged to the species H. aduncum. Our results support the hypothesis that infection with these parasites does not affect the condition of the fish host analyzed, and that body size and depth are major drivers in determining infection levels with Anisakid and Raphidascaridid nematodes. [ABSTRACT FROM AUTHOR]

The genus Eustrongylides Jägerskiöld, 1909 includes parasitic nematodes (Dioctophymatidae) affecting various fish species and piscivorous birds of freshwater ecosystems. Currently, there is little information on the molecular characterization of E. excisus based on nuclear ribosomal internal transcribed spacer (ITS) rDNA regions. However, before the present study, there had been no reports of characterizing the E. excisus using nuclear small subunit ribosomal RNA (SSU rRNA) and mitochondrial cytochrome c oxidase subunit I (COI) genes sequences. In the present study, Eustrongylides spp. larvae were collected from pike-perch Sander lucioperca (L.) in Northern Turkey, and characterized by sequencing of ITS regions, SSU rRNA, and COI markers. Larvae herein morphologically identified as the fourth stage of Eustrongylides spp. were genetically identified as E. excisus based on the ITS sequence analysis. This study is the first record of SSU rRNA and COI sequences for E. excisus in GenBank. This is also a molecular characterization of E. excisus for the first time in Turkey. The ITS, SSU rRNA, and COI sequences of E. excisus can be used to establish the phylogenetic relationships of Eustrongylides species from Turkey and worldwide for further studies. [ABSTRACT FROM AUTHOR]

Nematodes of the genus Physaloptera are globally distributed and infect a multitude of hosts. Their life cycle involves orthopterans and coleopterans as intermediate hosts. The morphological characters alone are inadequate to detect and differentiate Physaloptera spp. from its congeners. Moreover, molecular studies are limited to compare them precisely. The present communication reports the first molecular phylogenetic characterization of feline Physaloptera spp. from India based on mitochondrial cytochrome c oxidase subunit 1 (COX1) and small subunit ribosomal DNA (18S rDNA). The nematodes were first isolated from the stomach of adult stray cats during necropsy examination. Based on the gross and microscopic characters, the worms were identified as P. praeputialis. Morphological identification was further confirmed through PCR targeting the barcode region of the mitochondrial cytochrome c oxidase subunit I (MT-COI) gene, using nematode-specific primers cocktail followed by species specific primers targeting partial COX1 and 18S rRNA genes. Generated sequences were submitted in NCBI GenBank (MW517846, MW410927, MW411349), and phylogenetic trees were constructed using the maximum likelihood method. When compared with other sequences of Physaloptera species across the globe, the present isolates showed 85.6–97.7% and 97.3–99% nucleotide homology based on COX1 and 18S rRNA gene, respectively. BLASTn analysis revealed a strong identity to other Physaloptera spp., and the phylogenetic tree placed all Physaloptera spp. in the same cluster. This study again indicates the usefulness of molecular techniques to substantiate the identity of species that may lack adequate descriptions and impart new insight for the potentially overlooked significance of P. praeputialis infections in felines. [ABSTRACT FROM AUTHOR]

Procamallanus is a species-rich genus of parasitic nematodes of marine, brackish, and freshwater fishes, occurring also occasionally in amphibians and reptiles. In the Neotropical region, this genus is highly diverse, with species described from a wide range of fish families. In this study, we reassess the taxonomic status of Procamallanus rebecae with molecular and morphological data and describe a new species endemic to Nicaragua and Costa Rica. We analyzed all Procamallanus isolated from fish from the Nicaraguan lakes and some rivers in Costa Rica after an exhaustive analysis of their freshwater fish endoparasite fauna. Procamallanus rebecae is a host-specific parasite of Middle American cichlids, previously reported in southern Mexico, Nicaragua, and Costa Rica. We therefore compared these Central American specimens with individuals of P. rebecae collected in cichlids from southeastern Mexico using two genomic regions (28S rDNA and mitochondrial cytochrome oxidase subunit 1, COI). We found high levels of sequence divergence between Procamallanus from the two geographical regions, with up to 9.8 and 10.5% for both genetic markers, respectively. We also analyzed their morphology and found conspicuous differences in the shape of the mouth and the structure of the female cauda. We therefore describe the specimens of Procamallanus from Central American cichlids as a new species. Both Procamallanus species occur in different cichlid species and are allopatrically distributed. The host specificity and ancient association patterns between cichlids and Procamallanus and the jointly colonization of both hosts and parasites during their northern dispersal from South America are briefly discussed. [ABSTRACT FROM AUTHOR]

The genetic diversity of Syphacia nematodes (intestinal parasites of rodents) was studied in the hybrid zone of two sister species of common voles, Microtus arvalis and Microtus obscurus, in the Oka River valley, east of Moscow. Syphacia nematodes of other rodent species (Microtus rossiaemeridionalis, Alexandromys oeconomus, Sylvaemus uralensis, and Apodemus agrarius) that inhabit the area were also studied. Phylogenetic trees for the studied nematodes were inferred from the analysis of nuclear ITS1+5.8S+ITS2, LSU rDNA, and mitochondrial CO1 gene partial sequences. Syphacia nematodes of the studied area form three well-defined clades in the phylogenetic tree of this genus. Morphological analysis revealed similarities between the obtained sequences with those of known Syphacia species from the GenBank database, which enabled identifying these three clades up to the species level: S. montana, S. agraria, and S. frederici. Russian haplotypes of Syphacia are different from West European and East Asian haplotypes with pronounced genetic distances. A high level of specificity was reported for two of these three species (S. frederici, only in Sylvaemus uralensis; S. agraria, only in Apodemus agrarius). S. montana was found in different species of voles. Remarkably, S. montana specimens from M. arvalis and M. obscurus were genetically uniform, while S. montana, specimens from hybrids between these two species formed a separate clade distant from those originating from non-hybridised hosts. [ABSTRACT FROM AUTHOR]

Parasites can be used as biological tags to assess stock structures in various marine fish species. In the present study, the species composition and infection levels of parasitic nematodes of the genus Anisakis in the skipjack tuna Katsuwonus pelamis were examined in the Northwest Pacific and adjacent seas. A total of 867 third-stage larvae of Anisakis were collected from 112 skipjack tunas captured around Japan and in other subtropical localities. All larvae were identified as A. berlandi, A. pegreffii, A. simplex (s.s.), A. typica, and A. physeteris (s.l.) by the direct sequencing of the mitochondrial cox2 gene and real-time PCR assays targeting the nuclear ITS region. Anisakis species composition differed among northeastern Japan, the Sea of Japan, and other areas (central Japan, the Nansei Islands, and subtropical region), which is largely concordant with previous stock discrimination of skipjack tuna. Molecular phylogenetic analysis resulted in two intraspecific genetic groups in A. simplex (s.s.), one of which occurred almost exclusively in northeastern Japan. This could be a useful indicator for stock discrimination. Skipjack tunas from northeastern Japan were also characterized by a remarkable variety in the intensity of A. simplex (s.s.), suggesting the commingling of individuals with different migration patterns. This idea might be further justified by the geographic distribution of two genetically distinct groups of A. physeteris (s.l.). [ABSTRACT FROM AUTHOR]

Two species of intestinal Capillariidae were hitherto known from the Neotropic cormorant Phalacrocorax brasilianus, Baruscapillaria spiculata (Freitas, 1933), and Baruscapillaria appendiculata (Freitas, 1933). The original descriptions are very short and brief, and further reports of both species are scarce and/or confusing. This paper provides a morphological redescription and molecular characterization, based on the partial 18S rDNA gene, of B. spiculata specimens parasitizing the Neotropic cormorant in two continental lagoons from Buenos Aires province, Argentina. Both morphological and morphometrical differences between B. spiculata and B. appendiculata are highlighted on the examination of available type material. Additionally, two previous reports of B. appendiculata from Mexico and Brazil are discussed. A phylogenetic analysis conducted on specimens of B. spiculata and 46 other capillariid isolates available from the GenBank demonstrated a sister-taxon relationship between our specimens and the type species of Baruscapillaria. But, at the same time, significant genetic distances between both taxa showed an interesting variability of the genus Baruscapillaria. The probable division of this genus into multiple genera could probably be confirmed through integrative studies including more species. [ABSTRACT FROM AUTHOR]

The nematode family Spirocercidae Chitwood and Wehr, 1932, comprises three subfamilies, Spirocercinae Chitwood and Wehr, 1932; Ascaropsinae Alicata and McIntosh, 1933; and Mastophorinae Quentin, 1970, which occur worldwide. Spirocercids infect canids and can cause severe illness. The crab-eating fox, Cerdocyon thous (Linnaeus, 1766), is a canid that inhabits most of South America, including Brazil and is a host for several parasitic worms, in particular, nematodes. However, few reports or genetic data are available on the spirocercids found in this host. In the present study, we describe a new species of Spirobakerus Chabaud and Bain 1981, from the intestine of two crab-eating foxes from two different biomes in Brazil. Spirobakerus sagittalis sp. nov. presents a) unequal spicules, with a long, thin left spicule with a lanceolated shape at the tip; b) a pair of sessile papillae and a median unpaired papillae located anteriorly of the cloaca, and c) a tuft without spines at the tip of the tail in females. The molecular phylogenetic analysis indicated that S. sagittalis sp. nov. is basal to the other species of the subfamily Ascaropsinae, which was not recovered as monophyletic. Our phylogenies also indicated that Spirocercidae is paraphyletic, given that Mastophorinae did not group with Ascaropsinae and Spirocercinae. We provide the first molecular data on the genus Spirobakerus and expand the molecular database of the spirocercids. However, further studies, including the sequences of other spirocercid taxa, are still needed to infer the relationships within this family more accurately. [ABSTRACT FROM AUTHOR]

The European eel Anguilla anguilla is listed as critically endangered by the IUCN. Among many threats, the introduced parasitic nematode Anguillicola crassus is suspected to alter the eels' swim bladder and jeopardize their reproductive oceanic migration. To date, gaining knowledge about the distribution and prevalence of A. crassus requires individual sacrifice (over 50,000 eels were sacrificed for epidemiology studies since 2010). This paper describes a non-lethal molecular protocol for identifying prevalence of A. crassus in A. anguilla, based on searching for A. crassus DNA in the feces of eels. Tests using three DNA microsatellite markers specific to the nematode showed that molecular detection provided similar results to visual examination of the swim bladder in up to 80% of the cases, and allowed for comparison of prevalence among sites. Easy to implement, this non-lethal protocol for detecting A. crassus could be valuable for management plans of this endangered species. [ABSTRACT FROM AUTHOR]

Adult Anisakis Dujardin, 1845 were found in two specimens of killer whale Orcinus orca and one specimen of franciscana Pontoporia blainvillei stranded from off the coast of Buenos Aires Province, Argentina. Genetic identification of the nematodes (N = 144) was performed by sequence analysis of the mitochondrial (mtDNA cox2) and the nuclear (nas 10 nDNA) gene loci. Anisakis pegreffii and Anisakis berlandi were detected in the two individuals of O. orca, while Anisakis typica and A. pegreffii were identified in P. blainvillei. Morphological and morphometric analysis also carried out on adult specimens of A. pegreffii and A. berlandi has allowed to underlining the usefulness of genetic/molecular markers in their recognition. This represents the first record of A. pegreffii in O. orca and P. blainvillei and of A. berlandi in O. orca. This is also the first sympatric and syntopic occurrence, as adults, of A. pegreffii and A. berlandi from the Austral Region of the Atlantic Ocean waters. These results provide insights into the knowledge of the host ranges and geographical distribution of these parasites in the basin waters of the region. Pontoporia blainvillei showed low abundance values of infection with Anisakis spp., which is the general pattern for coastal dolphins in the area, whereas O. orca harboured higher abundance of Anisakis spp. than those previously recorded among cetacean species in the Argentine Sea. Differences in the Anisakis spp. distribution and their parasitic loads, observed among the three host specimens, are discussed in relation to the oceanographic parameters, as well as to the host ecology. The usefulness of genetic/molecular markers in the recognition of adults of the sibling species A. pegreffii and A. berlandi with considerable overlapping in morphometric and morphological characters was underlined. The distribution of Anisakis species from Southwestern Atlantic waters is discussed in relation to their value as indicators for studies on the zoogeography of their hosts at a regional-scale level. [ABSTRACT FROM AUTHOR]

Sexually anomalous individuals, typically intersexes or gynandromorphs, bear a mixture of male and female traits. Twelve sexually anomalous individuals of the black fly Simulium (Gomphostilbia) trangense Jitklang, Kuvangkadilok, Baimai, Takaoka & Adler were discovered among 49 adults reared from pupae. All 12 sexually anomalous adults were parasitized by mermithid nematodes, although five additional parasitized adults had no overt external anomalies. Sequence analysis of the 18S rRNA gene revealed that the mermithids, possibly representing a new species, are related to Mesomermis spp., with genetic distances of 5.09–6.87%. All 12 anomalous individuals had female phenotypical traits on the head, thorax, forelegs, midlegs, and claws, but male features on the left and right hind basitarsi. One individual had mixed male and female genitalia. The findings are in accord with the trend that mermithid infections are associated with sexually anomalous adult black flies. [ABSTRACT FROM AUTHOR]

Wellcomia species (Oxyuridae, Syphaciinae) parasitise several families of rodents from Africa, Asia and America with diverse ecological characteristics. A new species of Wellcomia is described based on specimens obtained from the plains viscacha Lagostomus maximus (Chinchillidae) from Argentina. The description includes morphometric and ecological aspects and an emended diagnosis of the genus Wellcomia. In addition, a molecular characterisation (18S rRNA) and an exploratory analysis of the genetic distances of the species included in this genus are provided. The new species, Wellcomia hugoti n. sp., differs from other species of the genus in the morphology of the cephalic plate, the ventral rugose area in males and the vulva in females. The new species showed a low prevalence (7.7%) and a high mean abundance (73.8). The genetic distances detected do not allow a comprehensive assessment of the monophyly of the genus. This is the seventh record of this genus in rodents from the Americas, the second in rodents from Argentina and the first record for the family Chinchillidae. [ABSTRACT FROM AUTHOR]

Understanding the processes responsible for structuring communities has been a challenge in ecology, and parasite communities are an excellent system to address this issue. The use of different diversity metrics can help us to understand the determinants of the structure of parasite communities, and in this sense, functional diversity indexes make it possible to measure the variability of organism traits in communities. In this study, we investigate how host body size and habitat use influence the functional diversity of nematode parasite infracommunities. We collected and examined 213 individuals of 11 species of anurans in an area of the Brazilian Atlantic Forest, calculated Rao's quadratic entropy as a measure of functional diversity of parasite infracommunities, and tested if this index was related to host body size and habitat use with an analysis of covariance (ANCOVA). Anuran species varied in body size (from 1.80 to 10.35 cm) and habit use (arboreal, terrestrial, and semiaquatic), and in the functional diversity of parasite infracommunities (Rao's quadratic entropy ranged from 0 to 0.196). We observed that anurans with larger body size and terrestrial habit showed significantly greater functional diversity of parasites. We conclude that anuran characteristics drive the functional diversity of nematode parasite communities, and highlight the importance of using different diversity metrics to understand the determinants in the host-parasite interaction. [ABSTRACT FROM AUTHOR]

Filarioid nematodes are parasites of the tissues and tissue spaces of all vertebrates except fish. Females produce microfilariae that enter the host's blood circulation or skin and may cause ocular and neurological pathology, leading to important implications in veterinary and public health. The present work is the first investigation on Setaria labiatopapillosa conducted in Morocco to characterize the morphological features of both adult and microfilaria forms. Two adult female nematodes were found free in the thoracic cavity of a slaughtered 3.5-year-old (6 teeth) Moroccan enhanced cross-breed bull which was born and raised in Morocco. The worms were identified as S. labiatopapillosa by light microscope (LM) and scanning electron microscopy (SEM) on the basis of their characteristic features of the anterior and posterior parts of the worms. The two S. labiatopapillosa worms measured 90 mm and 105 mm in length and 0.55 and 0.64 mm in width, respectively. Microfilariae were detected in the fully developed eggs contained in the uterus of both nematodes. A detailed morphology of both the adult females and larvae of S. labiatopapillosa is described using LM and SEM. Although the origin of S. labiatopapillosa analyzed in the present study is unknown and there is currently no evidence that Setaria spp. have invaded Morocco, further surveillance is warranted to determine the incidence of setariasis, identify its vectors, and take appropriate measures to protect the livestock and cattle industry of the country. [ABSTRACT FROM AUTHOR]

This study aimed to determine the integrative characterisation of nematodes from three species of edible flathead fishes (Scorpaeniformes: Platycephalidae) in New South Wales, Australia, and describe nematode communities within three species of flatheads. Tiger (Platycephalus richardsoni (Castelnau); n = 20) and sand flatheads (Platycephalus bassensis (Cuvier); n = 20), sourced from the Nelson Bay area, and dusky flathead (Platycephalus fuscus (Cuvier); n = 20) from the Manning River, Taree, were examined for the presence of nematodes. The nematodes were initially classified morphologically as 12 different morphotypes belonging to the families Anisakidae (Anisakis types I, II, and III, Contracaecum type II, Terranova types I and II), Raphidascarididae (Hysterothylacium types IV, VI, VIII, and H. zhoushanense larva), and Gnathostomatidae (Echinocephalus sp. larva), Capillariidae (Capillaria sp.), followed by genetic identification through sequencing of the internal transcribed spacer (ITS-1, 5.8S, ITS-2) regions. Phylogenetic analyses revealed the evolutionary relationship between the identified larval specimens in the present study with available GenBank larval and adult nematodes. Sand flathead was 90% infected with nematodes followed by tiger flathead at 85% and dusky flathead at 15%. Nematodes infecting estuarine dusky and oceanic sand and tiger flatheads contrasted markedly. The analysis of similarities (ANOSIM) showed significant differences (p < 0.001) in the composition of taxa within nematode communities between the three species of flatheads (global R = 0.208) with the highest difference being between sand and dusky flatheads (R = 0.308, p < 0.001). The findings of the present study provide a foundation for future investigations of the community composition, life cycles, and distribution of nematode populations in edible fish in Australia and explore and clarify their significance to public health. [ABSTRACT FROM AUTHOR]

The northern fur seal (NFS), Callorhinus ursinus (Mammalia: Otariidae), is a marine mammal species included into the IUCN Red List as the vulnerable species which population is dramatically declining. A significant amount of parasitological data collected previously and our recent data allowed us to clarify the list of NFS metazoan parasites and to perform a comprehensive analysis of the gastrointestinal helminth community. Gastrointestinal tracts from 756 NFSs (3- to 4-year-old males) were collected during the annual Aleut subsistence harvests in July–August of 2011–2014 from five separate rookeries on St. Paul Island, Alaska. Totally, 27,625 specimens of helminths and approximately 1000 nasal mites were collected and identified. Detailed analysis of the previously published and newly obtained data revealed 32 species of metazoan parasites, including trematodes (6 species), cestodes (4), nematodes (9), acanthocephalans (9) and arthropods (4). The gastrointestinal helminth community of newly studied NFSs comprised 19 species including trematodes (4), cestodes (3), nematodes (5) and acanthocephalans (7). Temporal changes in the helminth community structure were small but statistically significant. Gastrointestinal helminth infracommunities comprised from 1 to 10 species (average of 4). Small but significant correlation was found between the abundances of acanthocephalans (Corynosoma similis and C. strumosum), nematodes (Contracaecum osculatum, Pseudoterranova spp.) and cestode Diphyllobothrium tetrapterum. [ABSTRACT FROM AUTHOR]

Nematodes and coccidia are major pathogens causing parasitic infections in livestock production. This study aimed to determine the prevalence and seasonality of gastrointestinal helminths and coccidia in communal sheep grazing in humid, semi-humid and arid zones of the Eastern Cape Province. A total of 3299 faecal samples were collected from sheep between January 2012 and December 2015. Of the collected roundworm species (faecal eggs and faecal cultures), Haemonchus contortus was the only species found. The prevalence of gastrointestinal parasites was significantly higher in the humid zone (H. contortus 81% and coccidia 37%), followed by a semi-humid zone (H. contortus 75% and coccidia 22%) and the arid zone was the lowest (H. contortus 71% and coccidia 14%). Haemonchus contortus had significantly higher faecal egg counts (FEC) during spring (1465.73 ± 143.56) and summer (1418.73 ± 160.73) and the lowest during autumn (496.67 ± 219.13) and winter (352.05 ± 164.44) in all agro-ecological zone. The humid zone had significantly higher FEC in seasonal occurrence of H. contortus and coccidia compared with other agro-ecological zones (P < 0.05). There was no significant difference (P > 0.05) observed in the seasonal occurrence of H. contortus species in arid zone. Surprisingly, higher coccidia counts (352.17 ± 43.58) during 2012 winter season in humid zone and in summer season (0.00 ± 559.72) of 2013 in the semi-humid zone than other agro-ecological zones. However, agro-ecological zone differences and seasonal variations had an influence on H. contortus and coccidia distribution and abundance. This study confirms that helminths and coccidia are major causative agents causing parasitic infections in livestock production, and therefore, good animal health management practices including proper hygiene should be followed to prevent parasitic infection in small ruminants. [ABSTRACT FROM AUTHOR]

To ensure that meat from livestock and game is safe for human consumption, European legislation lays down rules for mandatory testing. Helminth larvae are a category of zoonotic foodborne pathogens that can contaminate meat. Among helminths, the only zoonotic nematode regulated in Europe regarding meat inspection is Trichinella spp.. It is precisely during Trichinella testing that other potentially zoonotic larvae can be found. Due to current lack of tools, their identification is often very complicated. Nematode larvae other than Trichinella, recovered from artificial digestions of pig and wild boar muscles from France and Germany, were subjected to a newly developed two-step identification scheme, which includes both morphological examination and molecular assays. The first step is a general orientation towards a broad taxonomic group; the second step consists of targeted identification based on the results of first step. Different parasites were identified, some of which were not zoonotic such as Metastrongylus spp. and Angiostrongylus vasorum, but others are known to be zoonotic such as Toxocara cati, Ascaris suum, and Uncinaria stenocephala. The strategy is efficient for the identification of nematode larvae recovered from muscles but could also be applied for larvae from other sources. [ABSTRACT FROM AUTHOR]

The taxonomy of Hysterothylacium genus in Mediterranean waters remains incomplete and unresolved. The aim of the current study was to investigate the morphological and molecular identification of selected species of Hysterothylacium larvae in marine fish from the Tunisian Mediterranean coasts. A total of 192 marine fish samples were examined. In total, thirty-seven third-stage larvae of Hysterothylacium were morphologically identified as Hysterothylacium type V. In the present study, representatives of this type from the Mediterranean Sea were genetically characterized for the first time by sequencing the rDNA ITS (ITS1-5.8S-ITS2) regions and mtDNA cox2 gene. This study represents the first report of Hysterothylacium type V from the Mediterranean Sea. We also report Mullus barbatus, M. surmuletus, and Pagellus erythrinus as new hosts for this larval type. Based upon molecular and phylogenetic analyses considering the rDNA ITS regions, the Hysterothylacium type V described here was classified as a new genotype, named Genotype B. The valid genetic data of the described Hysterothylacium type V in the present study can be used to establish the phylogenetic relationships among Hysterothylacium species from the Mediterranean Sea and worldwide for future research. [ABSTRACT FROM AUTHOR]

Aelurostrongylus abstrusus (Nematoda, Metastrongyloidea) causes verminous pneumonia in cats worldwide. This study evaluated the seroprevalence of A. abstrusus antibodies in 220 stray and free-roaming cats from insular (Mykonos, Crete, Skopelos) and continental (Thessaloniki, Attica) Greece. The results were compared with morphological and biomolecular identification of first-stage larvae (L1) in faeces. Positive cats were observed in all 5 areas: 13/97 (13.4%), 1/32 (3.1%), 7/26 (26.9%), 3/18 (16.7%) and 5/47 (10.6%) cats tested positive for A. abstrusus L1 by Baermann examination, and 33/97 (34.0%), 7/32 (21.9%), 6/26 (23.1%), 3/18 (16.7%) and 11/47 (23.4%) were seropositive, in Mykonos, Crete, Skopelos, Thessaloniki and Attica, respectively. Troglostrongylus brevior L1 were found in 12/97 (12.4%), 3/26 (11.5%) and 2/47 (4.3%) cats from Mykonos, Skopelos and Attica respectively. Six of the 220 cats (2.7%), i.e. 4/97 (4.1%) from Mykonos and 2/26 (7.7%) from Skopelos, shed L1 of both A. abstrusus and T. brevior. Sixty samples were ELISA-positive (27.3%, 95% CI: 21.5–33.7%), of which 21 (35%) tested copromicroscopically positive (19 monospecific infections and 2 mixed with Troglostrongylus brevior), and 5 were positive for T. brevior L1 only. Among seronegative cats (n = 140), L1 of A. abstrusus were additionally detected in 8 (5.7% out of 140) cats (i.e. 4 monospecific infections and 4 mixed with T. brevior), and in 6 (4.3% out of 140) cats, L1 of T. brevior as monospecific infection were detected. This study confirms the presence of lungworms in Greece and suggests that the number of cats infected with/exposed to metastrongylids is higher than detected by faecal examinations. [ABSTRACT FROM AUTHOR]

Due to the increasing consumption of platinum (Pt), especially in automobile exhaust catalysts, environmental concentrations of Pt are of emerging concern worldwide. Limited information exists on environmental concentrations, particularly in Pt mining regions, while South Africa is the world's main supplier of Pt. Moreover, other metals are also released as by-products of Pt mining, which might also cause environmental concern. Certain fish parasite taxa have the ability to accumulate metals orders of magnitude higher than their hosts and can be used to reliably detect metals with naturally low abundance. Studies on Pt accumulation in parasite-host systems are limited. Therefore, the aims of the present study were (1) to determine the accumulation of a variety of metals (cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), platinum (Pt), and zinc (Zn)) in helminth fish parasites compared with their hosts from a reference site and an impoundment impacted by Pt mining activities; (2) to assess whether there is a difference between bioaccumulation of metals in infected and uninfected hosts, as well as between hosts with different infection intensities; and (3) to compare the biomarker responses (acetylcholine esterase activity (AChE), metallothionein content (MT), catalase activity (CAT), reduced glutathione content (GSH), malondialdehyde content (MDA), protein carbonyls induction (PC), superoxide dismutase activity (SOD), and cellular energy allocation (CEA)) between infected and uninfected hosts. The cestode Atractolytocestus huronensis accumulated significantly higher concentrations of Cr, Ni, and Pt than their host Cyprinus carpio, while the nematode Contracaecum sp. accumulated significantly higher concentrations of Pt and Zn than their host Clarias gariepinus. Infected fish showed lower metal concentrations compared to uninfected fish, while the parasites had no significant effects on their hosts' biomarker responses. The parasites demonstrated the bioavailability of metals derived from Pt mining activities and their ability to resist its toxic effects. Thus, these parasites are promising sensitive accumulation indicators for Cr, Ni, Pb, and Pt contaminations from Pt mining activities. [ABSTRACT FROM AUTHOR]

A collection of nematodes from the Muséum National d'Histoire Naturelle (National Museum of Natural History), Paris, France, was studied. The nematodes had previously been collected from a range of marine fish hosts. The aim of this study was to investigate the identity of these nematodes. Detailed body measurements of the nematodes were taken via light microscopy and where possible first and second internal transcribed spacers (ITS-1 and ITS-2) of ribosomal DNA were subjected to PCR, purified and sequenced. Six species and three larval types were found from a range of fish species and included 13 new host records and two new geographical records. Of the taxa found, Hysterothylacium kajikiae is the only species which may have zoonotic potential. The majority of host fish in this study are edible species, commercially and recreationally fished and frequently incorporated into the cuisine of New Caledonia as raw fish dishes. This study will allow better understanding of the diversity, life cycles, distribution and host-parasite relationships in the New Caledonia area. [ABSTRACT FROM AUTHOR]

Marsupials of the genus Didelphis, such as black-eared opossums (Didelphis aurita), are common synanthropic animals in urban areas of Brazil. These marsupials are frequently parasitized by numerous helminth species, including ancylostomatid nematodes. This study aimed to report the occurrence of Ancylostoma caninum in black-eared opossums captured in an urban environment of Southeastern Brazil and discuss the potential impact of these findings for public health. From January to June 2019, we collected fecal samples from 49 restrained opossums and evaluated by a simple flotation method; Helminth eggs were observed at different magnifications and identified according to morphological and morphometric features. Genomic DNA was extracted from Ancylostomatidae eggs and screened by duplex PCR for Ancylostoma spp. and Necator americanus using primers that amplify a region of internal transcribed spacer 2 and the 28S ribosomal RNA (ITS2-28S rRNA). Ancylostoma spp. eggs were detected in 65.3% (32/49) of the animals. Sequence analysis revealed 100% homology with A. caninum sequences from GenBank. Our results demonstrate a new host-parasite interaction for A. caninum, suggesting that black-eared opossums may participate in the zoonotic cycle of this parasite in urban areas of Brazil. [ABSTRACT FROM AUTHOR]

Contracaecum rudolphii (s. l.) is a complex of sibling species of anisakid nematodes having the fish-eating birds belonging to the Family Phalacrocoracidae as final hosts. The great cormorant Phalacrocorax carbo sinensis is parasitized by C. rudolphii A and C. rudolphii B. Adults and L4 specimens of C. rudolphii (s. l.) (N = 3282) were collected in cormorants from brackish and freshwater ecosystems of Central Italy. Third-stage larvae of Contracaecum (N = 882) were obtained from the fish species Dicentrarchus labrax, Anguilla anguilla, Aphanius fasciatus, Atherina boyeri, Leuciscus cephalus, Barbus barbus, and Carassius carassius captured in the same geographical areas of cormorants' standings. Contracaecum rudolphii A and C. rudolphii B were identified by a multilocus genetic approach: allozymes, sequences analysis of the mtDNA cox2, and ITS region of rDNA gene loci. Differential distribution of the two parasite species was observed in different aquatic environments. Contracaecum rudolphii B outnumbered C. rudolphii A in wintering cormorants from freshwater ecosystems; the opposite trend was found in cormorants from brackish water. Analogously, C. rudolphii A larvae were more prevalent in brackish water fish, while C. rudolphii B larvae were found infecting only freshwater fish. The findings seem to confirm that C. rudolphii A and C. rudolphii B would have a life-cycle adapted to brackish and freshwater environments, respectively. A differential feeding behavior of wintering cormorants, the ecology of the infected fish species, and abiotic factors related to early stages of the parasites are supposed to maintain the distinctiveness of the two parasite species' life cycles in the two different aquatic ecosystems. [ABSTRACT FROM AUTHOR]